Australia’s Media Entertainment and Arts Alliance (MEAA) has called on journalists to continue investigating government and corporate surveillance following disclosures by NSA whistleblower Edward Snowden in Australia’s annual press freedom report.

The report warns that public confidence has been undermined by revelations of mass surveillance sparked by the disclosures, and urges journalists to improve their understanding of surveillance in the wake of the revelations.

“The treatment of whistleblowers such as Chelsea Manning and the threats made to Edward Snowden and the detaining of David Miranda are causes of grave concern for journalists,” the report said.

“The manner journalists can work with their confidential sources, protect the confidential nature of their sources and the information they provide; work on their stories without intimidation and publish important information in the public interest have all been undermined by the events above.”

Whistleblower protection, defamation law, suppression orders and attacks on public broadcasters are among the areas where the alliance urges changes.

The report also flags the government’s culture of secrecy surrounding asylum seeker policy as a considerable press freedom concern because of the “militarisation of customs and immigration activities”.

“MEAA believes the silence surrounding the activities of Australian vessels and personnel in contact with asylum seekers and boats is at odds with the public’s right to know.”

State and federal freedom of information acts also need urgent review, according to the report. The MEAA said there were “ongoing concerns over the silence surrounding government and the reluctance of public servants to release information”.